Mobile Number Portability (MNP) service means that a mobile subscriber does not change the original number of its mobile station in Integrated Services Digital Network (ISDN) when a subscribed network is changed. Based on the MNP service, a new subscribed network allocates a new International Mobile Subscriber Identification (IMSI) number to the Ported-in mobile subscriber, and the ported-in mobile subscriber enjoys all the services of the new subscribed network.
At present, typical signaling intercommunication is message intercommunication between a Code Division Multiple Access (CDMA) mobile communication network and a Global System for Mobile Communication (GSM) network. Taking that GSM transmits a message to CDMA and signaling intercommunication is performed at the CDMA network side as an example, the message procedure includes:
step 11, a GSM Mobile Switching Center (MSC) sends a Mobile Original (MO) message to a GSM Short Message Service Center (SMSC); and a target subscriber is a CDMA subscriber;
step 12, the GSM SMSC returns a response to the GSM MSC;
step 13, the GSM SMSC sends a route request to a CDMA SMSC;
step 14, the CDMA SMSC simulates a Home Location Register (HLR) to return a response to the GSM SMSC, wherein MSC address is the address of the CDMA SMSC in the GSM network;
step 15, the GSM SMSC initiates a Mobile Terminal (MT) delivery operation to the CDMA SMSC;
step 16, the CDMA SMSC simulates the MSC to receive the MT message and transmits a response to the GSM SMSC; or the CDMA SMSC returns a response to the GSM SMSC after the CDMA SMSC sends a message to the CDMA HLR;
step 17, the CDMA SMSC sends a route request to the CDMA HLR;
step 18, the CDMA HLR returns a response to the CDMA SMSC;
step 19, the CDMA SMSC sends the MT message to the CDMA MSC; and
step 110, the CDMA MSC returns a response.
During the signaling intercommunication based on the Mobile Number Portability service, a called terminal to which a message is delivered from a sending may be a third-party network subscriber, and the procedure above does not consider the short message intercommunication in the Mobile Number Portability service, so it cannot be applied to the Mobile Number Portability service.